Impulse voltage device



Dec. 6, 1949 W. H. BOLDINGH IMPULSE VOLTAGE DEVICE Filed July 8, 1946 mwwmzwzozmvm I N V EN TOR.

BY i W AT TUE/V151? Patented Dec. 6, 1949 IMPULSE VOLTAGE DEVICE Willem Hondius Boldingh, Eindhoven, Netherlands, assignor to Hartford National Bank and Trust Company, Hartford, Conn., as trustee Application July 8, 194:6,Serial No. 681,909 In the Netherlands March 22, 1943 Section 1, Public Law 690, August 8, 1946 Patent expires March 22, 1963 6 Claims. 1

Impulse voltage devices consist of a plurality of condensers which are connected in parallel through the intermediary of resistances and in series through the intermediary of spark gaps. The condensers are charged by a source of direct current. At a determined voltage the spark gaps break down and the charge of the condenser flows away through a resistance.

Devices of this type are usually very bulky so that they take up much room.

During the charge the successive condensers acquire a steadily increasing voltage with respect to earth. For this reason one has proceeded to mount the condensers in metal cases and to arrange the latter in stages on an insulating base so that the insulation resistance increases in accordance with the voltage of the condensers relatively to earth.

In another form of construction the condensers are provided with an insulating envelope, owing to which they could act at the same time as supporting constructional elements. For impulse voltage devices of high power the condensers are sometimes distributed over more than one, for example, four columns. By the interposition of insulators, for example, a helical structure is obtained in this case. In view of a satisfactory spatial potential distribution and of a practical construction the condensers are arranged in the various columns at an equally higher level with respect to the condensers which precede in the circuit arrangement, the resistances and the spark gaps being housed in the space bounded by the columns.

It has also been proposed already to superpose all the condensers on one another in a common envelope consisting of insulating material, owing to which a column-shaped structure is obtained. This construction requires a, comparatively large base but the height of the column increases with the voltage. The consequence thereof is, that the voltage which can be generated with the aid of this installation is limited by the rigidity of the column, which is insuflicient in the case of a large height. In this known device each con- 2 during the process of charging in the direction of the axis of the column.

This form of construction has the drawback that the constructional height of the column must be larger than is required in view of the dimensions of the condensers, for the dimensions of the column in the direction of the length, i. e. the height of the installation, are not only determined by the height and the number of the condensers utilized. Two successive condensers, which are superposed on one another in the column, must be separated from one another by an insulating layer, which is calculated for the direst-current voltage up to which the condensers are charged. The constructional height required for each condenser consequently becomes twice as large as would be necessary in view of the insulation length required for the charging voltage.

The present invention has for its object to make in such an impulse voltage device which comprises condensers which are connected in parallel through the intermediary of resistances and in series through the intermediary of spark gaps, a more efiicient use of the room available in the column. It is thus achieved that with the same height of the installation use may be made of a larger number of condensers and that consequently the impulse voltage may be accordingly higher.

According to the invention, use is made of two or more than two condensers which are arranged in the column in such manner that the potential differences brought about by the application of the charging voltage, substantially occur in the transverse direction and that those points of the condensers which are located in the column above one another in the axial direction have during the charging process of the condensers equal or substantially equal potentials. Each condenser may consist in this case of elementary condensers which have been united so as to form a stack or of a plurality of such stacks, which are located parallel to one another, whilst the condensers are arranged in the column in such manner that the direction in which the potential difference across the condensers occurs during the charging period is perpendicular to the axis of the column and the corresponding connecting terminals of the various condensers are located in the axial direction above one another. With this arrangement of the condensers all points which have equal or substantially equal potentials during the charging period are located in the same plane.

Owing to the fact that during the charging of the condensers there occurs substantially no po- A very advantageous form of .eonstructionis obtained if each condenserlis .placeddn a/case and the separate cases are united to fpr ma col umn. If there occurs a fault due to deterioration of one of the condensers, this condenser can easily be replaced by another. It is only-necessary to substitute a new condenser case for the 'faulty part.

direction of the column. The insulation distance between the condensers is consequently determined by the impulse voltage and may be appreciably smaller than ifthere occurs a similar .loading of .the insulation distance with directcurrent voltage.

The cases I are provided with flanges 9 of insulating material, which serve for the attachment of'the resistances and the spark gaps 6 which are arranged outside'the cases, a compact unit of -.,the smallest possible dimensions being thus ob- .tained.

The invention will be explained more fully with reference to the accompanying drawing wherein Fig. 1 representsthe'k'nown device, wherein use is made of large fiat condensers and Fig.- 2- represents diagrammatically, by way of example,;a device according to the invention.

In thedevice accordingto Fig'l'the condensers are surrounded by a cylindrical envelope I of-insulating material which is arranged on a'baseplate 2. In the example shownthe column comprises five stages of'the-impulse voltage device according to the system of connections of Marx. If desired, this number inaybe taken larger or smaller so-faras such is admissible-in view of the stability of the column. The useof a plurality of stages increases the drawback that, if any of the condensers getsout of order, theentire column has to be taken to pieces or to be replaced by a newone. The column-is provided with a ring;

which has a large surface area in orderte reduce the risk offiashing over along'the surface ofthe column duringthe discharge ofthe condensers.

Thecondensers; as well as the enargingresistances 5 and the spark gaps i6 arediag'rammatically represented.

As may be seen from thefigure, the mounting height of each stage isqdetermined by twicetne direct-current voltage for charging tnecondens ers, i. e. once for theheightof the condensers'be tween the points or and'bi, a2 and be, its and be,

etc. and once for the insulation between tneseparate condensers that is tosay between the points in and cm, In and a3,b3 andagetc ln principle only half of the height is available fer the condensers.

I'he loading with direct-current voltage requires a much greater insulation lengththanthe loading exclusively with impulse voltage, so-that with the device according totheinvention and with the same mounting height thejroom available for housing thecondensers is nuchlarger, as maybe seen from Fig. 2. This fi gureshows,

likewise diagrammatically, the arrangement of the condensers l, theresistances 5 and thelsparik gaps 8. The device consists of ,separate units. Each unit consists of a case 1 which comprises a bottom 8 and which is madeiof insulating material, and contains a condenser. .ns appears. from the drawing, thevoltage increases, from the points a towards thepoints h, i. e. intlietransverse di rection. The whole of the diameter, of the column lit is available forthe insulation between the two I connecting terminals of each condenser. v The points which have the same potential during the charging of the condensers are located perpendicularly above one another, sothat substanti ally no loading With dire irwrr n .vo ta edees. o u between the various cross-sections in the axial ing plates in the other The units may be mounted and taken to pieces .il a simple manner, so that it is easily possible to arrange the generator at another place and, in the case. of disturbances, to eliminate the fault by replacingmhe faulty unit by a fresh one.

, ,Ifhecondenser present in each unit is built up from one or more stacks which consist of a plurality of elementary condensers connected in series. The various stacks are connected in paral- '1el,'which gives rise to the production of the surfaces of equal potential. The units must be arranged in the column relatively to one another in such manner, that the corresponding equipotential surfaces'foi'm part of a common potential surface, owing to which no potential difierences or only slight potential diiierences'are produced during the charging of the condensers in the direction of th e length of the column.

What I claim is: 1. Animp'ulse generatoradapted for energiz ation bye. direct-current source, said generator comprising an insulatingcolumn, a plurality of P condenserseach constituted by a pair of parallel plates, said condensers being colinearly arranged at spaced positions in the axial directionwithin saidcolummeach set of corresponding plates of said condensers beingaligned ina plane parallel to said axial direction, ,first resistance means external tosaidjco'lumn and interconnecting the corresponding platesin one of said sets, second resistance means interconnecting the correspond- ..ing plates in the other of said sets whereby said condensers are connected in parallel relation throughsaid' resistance means, and spark gap meansexternalfto said column and arranged to connect said condensers injseries relation.

2. An impulsegenerator adapted for, energization byafdirec't-current source, said generator cojmprisihg'an insulating column, a plurality of condensers each constituted by a pair of parallel plates, said condensers being colinearly arranged at spaced positions. in. the. axial direction within jsaidcolumn, each set of corresponding plates of said condensers beingaligned in aplane parallel to said a'xial directionfirst resistancemeans external tosaidcolumn and interconnecting the corresponding plates inone of said sets, second resistance means interconnecting the correspondof said sets whereby said condensers are connected in parallel relation, "spark gap means external to said column and arranged to connect said condensers in series relation, and insulating partitions within said column separating said condensers.

. 3. Animpulse generator adapted for energiza tion by a direct-current source, said generator comprising an insulating column, a plurality of condensers each constituted by apair of parallel plates, said condensers. being colinearly arranged at space d,PO5itions.in the axial direction Within saidrcolumn, each setofcorresponding vplatesof ,said condensersbeing,aligned in a plane parallel to said axial direction, first resistance means external to said column interconnecting the corresponding plates in one of said sets, second resistance means interconnecting the corresponding plates in the other of said sets whereby said condensers are connected in parallel relation, and spark gap means external to said column and arranged to connect said condensers in series relation, said column being defined by a plurality of cup-shaped casings of insulation material coupled together in stacked relation, each condenser being disposed in a respective casing.

4. An impulse generator adapted for energization by a direct-current source, said generator comprising an insulating column defined by a plurality of cup-shaped casings coupled together in stacked relation, each casing being provided with an outwardly projecting flange at one end thereof, a plurality of condensers each constituted by a pair of parallel plates and disposed within a respective casing of said column, said condensers being colinearly arranged at spaced positions in the axial direction of said column, each set of corresponding plates of said condensers being aligned in a plane parallel to said axial direction, first resistance means external to said column interconnecting the corresponding plates in one of said sets, second resistance means interconnecting the corresponding plates in the other of said sets whereby said condensers are connected in parallel relation, and a plurality of spark gaps each positioned external to said column and interposed between succeeding flanges of said casings, said spark gaps being arranged to connect said condensers in series relation.

5. An arrangement, as set forth in claim 4, wherein said first resistance means is constituted by a plurality of resistors each mounted between the succeeding flanges of said casings On one side of said column, and said second resistance means is constituted by a plurality of resistors each mounted between the succeeding flanges on the opposing side of said column.

6. An arrangement, as set forth in claim 4, wherein each casing at the flange end thereof is internally threaded and at the other end thereof is externally threaded whereby said casings defining the column are threadably intercoupled.

WILLEM HONDIUS BOLDINGH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,974,328 Bouwers Sept. 18, 1934 1,994,533 Pickard Mar. 19, 1935 1,997,064 Lusignan Apr. 9, 1935 2,014,219 Allibone Sept. 10, 1935 

